1. Field of the Invention
The present invention relates to an exhaust manifold including a curved end portion and at least two T-shaped portions connected to the curved portion through sliding fits, wherein the end portion and the T-shaped portions each are provided with a flange connection and a pipe connection, and wherein each T-shaped portion has a sliding fit connection piece.
2. Description of the Related Art
In an exhaust manifold of the above-described type, the flange connections of the T-shaped portions as well as of the end portion are connected to a head flange for connecting the exhaust manifold to a motor. In order to facilitate an expansion compensation, the end portion and the T-shaped portions are connected to each other through sliding fits. For this purpose, the sliding fit connection of a T-shaped portion engages over the end of the pipe connection of the end portion or over the end of the pipe connection of an adjacent T-shaped portion.
The T-shaped portions of the exhaust manifold are manufactured from a straight piece of pipe. For this purpose, using hydraulic high internal pressure, a connection piece-shaped bulge is produced which protrudes essentially perpendicularly from the pipe axis. This connection piece-shaped bulge is opened at the end thereof by means of a sawing cut. In this manner, the flange connection is manufactured. The sliding fit connection is formed by an end of the exit pipe.
The configuration described above has the disadvantage that the length of the flange connection is limited because of the fact that shaping is effected by means of hydraulic technology; specifically, the length is limited to at most one to two times the diameter of an exit pipe. A greater length of the flange connection could lead to an undue reduction of the thickness of the material. Consequently, the dimensions of other structural components must be adapted to the short flange length. This also makes it difficult to secure the head flange. Moreover, the assembly conditions for the exhaust manifold are impaired because the contact points for attaching the exhaust manifold to the motor are less easily accessible. Accordingly, the structural configuration and the technical use of such an exhaust manifold are limited.